There is no such thing as a perfectly-made video game, especially in a free-to-play game.
As such, a game such as Combat Arms has its own share of Glitches which is defined as an exploit in the game.
If a glitch gives a player a major advantage, it will often become a frequent trend by "glitchers" throughout the game. These different faults range from people able to go through boxes to even players dying prematurely when running on stairs! Major glitches are often fixed up in Patches.
In general, there are 2 main types of glitches: Exploitable and Non-Exploitable.
Exploitable glitches are those that are commmited by players, hense exploitable. These include wall glitches, box glitches, etc.
Non-Exploitable glitches are ingame errors, commonly reffered to as bugs. These include typos or spelling errors, faulty hitboxes, etc.